AUDI has revealed that achieving best-in-class handling for its eighth-generation A4 was matched by a desire to “out-ride” all its rivals as well.
Speaking at the B8-series A4 launch in Sydney last week, Audi AG’s project manager for dynamic steering Wolfgang Dick told GoAuto that Audi did not hold back in its development of the all-new small-medium prestige car.
He said that having new components and technology, a dedicated team of engineers and a directive from the top echelons of Audi to make the B8 A4 the best all-rounder in a fiercely competitive segment all combined to make the A4 a much better vehicle than initially imagined.
When development work commenced for the latest A4 in the latter part of 2004, Audi started by benchmarking what it believed to be the “best-in-class” BMW E46 and subsequent E90 3 Series for handling.
The original Lexus IS and Nissan’s Infiniti were other yardsticks at the time. However, as Mr Dick explained, this situation did not last very long.
“We have not only reached the BMW, I believe we have overtaken the BMW (in the area of balance) … so first it was a benchmark, but then when we saw the potential of our car and were given the opportunity to overtake it… from this point on the BMW ‘3’ was not the benchmark but as a pointer that we were on the right level.” According to Mr Dick, changing the position of the clutch and the gearbox in the new A4 was paramount in trying to achieve class-best handling.
This was necessary as the B8’s Modular Longitudinal Platform (MLP) includes a front axle that is pushed significantly more forward than in previous Audis, a wider front and rear track, and a longer wheelbase, for more even weight distribution.
This means that the drivetrain had to be mounted slightly more to the rear in the name of balance as well as greater space utilisation – Audi also claims that the A4 has class-leading rear legroom and boot space.
“It was hard work to change every gearbox we had – manual … automatic … the DSG that is coming in the future … and it affected the manufacturing line, as well as outside suppliers,” Mr Dick said.
“The agility of the B7 A4 was not so bad, but it was not as good as it now has to be.”Mr Dick said the choices Audi made for the outgoing A4 meant that it was inflicted with harder suspension components that “were not good for ride comfort”.
“So the second thing we did was to design a completely new front axle – to take the steering from the back and upper part of the axle (and reposition it) down to the front of the axle and at wheel level,” he said.
“Doing this also provides additional stiffness … as well as comfort and agility of the car.
“The third thing we did was the rear axle – it is not a new concept, but every part is new.”Audi based the multi-link rear suspension on the set-up employed by the current C6-series A6 model, but with extensive modification.
“This is good for future cars that come after – the derivatives of the new A4 … like the Cabrio and the Avant,” Mr Dick said. “It gives us the possibilities to tune a completely new set-up.”According to Mr Dick, BMW’s approach with the current (E90) 3 Series’ steering, while “quite good” suffers from too many compromises.
“BMW made a conceptual mistake with the double planetary gear, which has two main disadvantages that you have to prevent when you are designing a steering system: one is friction, which is totally bad for steering feel and centre-point feel, and the second is ‘backlash’ or play,” he said.
Mr Dick said he and his team had support from former Audi chairman Martin Winterkorn – now heading up Volkswagen – who is an engineer mindful of what needed to be done for the A4 to become truly competitive with BMW and others.
This required the wholesale abandonment of the previous A4’s architecture, which dates back to the 1994 B5 model that debuted the ‘A4’ badge (mid 1995 in Australia).
“(Martin Winterkorn) understands that the concepts of the past have reached their limits,” Mr Dick said. “He told us, ‘Make it different, show me how can you do better for the future – for the next 10 years.’”Audi did consider rear-wheel drive for the B8 as well, but only at the very early stages of development.
“During the concept phase of the project, yes, we discussed all types of completely different concepts – shall we do a rear-driven car, or shall we not? What are the advantages and disadvantages? Questions regarding other aspects as well – even down to whether we should use an electric parking brake (the new A4 does) … everything was discussed freely and included everybody’s input.
“We didn’t choose any other concept because they were not good for our car or the other cars (based on the MLP architecture) that are coming in the future.
“To make a car only (for keen drivers) is not the difficult part. What we have done now is … we’ve kept the sportiness and dynamics at the same level – this is the level that our customers want in our cars – but we have found a better compromise with our concept in comfort, because riding comfort is also one of the most important aspects of our cars.
“Building a much sportier car maybe takes one year and 50 engineers, and you don’t need (to undertake) a vast development. Finding a happy ride compromise is the much greater task … maybe taking (up) 40 times (the resources).
“And our car is the much better riding compromise.”Stressing that “I don’t want to sound like an American”, Mr Dick said that the combined effort of his team is what he is most proud of.
“Two and a half years of very hard work from the time work started on the steering and chassis control systems … six days a week from 11 in the morning up to 10 or 11 at night, on Saturdays, no holidays, without burning out. They are always giving me 150 per cent.”The Audi engineer is equally proud of the exact level of desired handling and ride comfort tuning achieved with so many all-new steering and front axle components, which not only proved to be a mammoth task in itself, but required a new level of interaction with people outside of their usual departments, in order to achieve the same goal.
So what is Mr Dick’s favourite B8 A4 combination?“If I could order one, it would be a B8 A4 Avant with the (upcoming) 150kW 2.0 TFSI quattro with manual and, of course, Audi dynamic drive.”